A day after Pope Francis grabbed headlines by pronouncing two flight attendants man and wife while flying 36,000 feet over Chile, the conservative Catholic commentariat on Friday questioned the legitimacy of the impromptu sacrament and warned it could cheapen the church’s marriage preparation down the line.

“Do you know what’s a ‘marriage’ ripe for annulment?” tweeted the traditionalist blog Rorate Caeli. “One celebrated apparently on a whim in an airplane whose celebrant cannot even be sure if parties are validly baptized.”

For those who missed the news, Francis on Thursday presided over what the Vatican said was the doctrinally and canonically legitimate wedding of Paula Podest and Carlos Ciuffardi, two flight attendants from LATAM flight 1250 that brought the pope, his delegation and travelling press from Santiago to the northern city of Iquique.

As the happy couple told journalists after the fact — and after serving breakfast — they had hoped to just get a blessing from the pope. They told him that they had been married civilly in 2010, but that their plans for a church wedding fell through when an earthquake hit.

As Ciuffardi told it, the pope proposed that he marry the couple right there, in part to motivate other couples to contract a church wedding at a time when more and more couples are merely cohabitating.

“He told me it’s historic, that there has never before been a pope who married someone aboard a plane,” Ciuffardi told reporters from the back galley.

The surreal scene had the effect — at least temporarily — of giving Francis a bit of a reprieve after his visit to Chile was dominated by a church sex abuse scandal.

Canon lawyer Ed Peters, a consultor on the Vatican high court but a frequent critic of Francis, questioned whether a host of church laws were followed, including the requirement that the couple undergo pastoral counseling and that the church have evidence that there were no obstacles to the marriage.

In a follow-up blog post Friday, Peters noted a Chilean media report from December saying the couple was hoping for an airborne wedding presided over by Francis, suggesting the portrayal of the surprise ceremony was anything but. Ciuffardi said Chilean reporters had suggested it before the fact, but he insisted he and Podest were only looking for a papal blessing, and that nothing was confirmed until they were airborne.

Conservative blogger Phil Lawler mused that priests might now have a harder time trying to properly prepare Catholic couples for marriage, now that Francis had set the papal precedent of completing the process between takeoff and landing.

“Does he ask them to reflect seriously on their commitment? Nope,” Lawler wrote at Catholic Culture. “Does he question them about their years of cohabitation? Evidently not. Does he hear their confessions? Not likely. Plan a dignified ceremony? Not at all.”

To be sure, the naysayers all hail from the Anglo-Saxon blogosphere, which is among the most vocal in criticizing Francis, especially on issues of marriage.

Francis has split the church over his cautious opening to allowing divorced and civilly remarried Catholics to receive Communion, so any issue related to marriage is particularly sensitive.

At The Tablet, a more liberal leaning British weekly, Vatican correspondent Christopher Lamb suggested that the airborne nuptials were part of the “paradigm shift” that Francis is trying to press in the church.

“It’s not that the pope is doing away with the need for rules, for canon law or for paperwork, but rather ensuring it is correctly prioritized,” Lamb wrote. “For the pope, these things must support the spread of the Gospel, and not become like the thorns that grow up and strangle the seeds in the parable of the sower.”